Dietary calcium inadequacy may be a contributing cause to osteoporosis for some populations. For example, a positive correlation between calcium intake and bone mass has been found across many age groups. It has been suggested that the level of calcium intake early in life directly influences the peak bone mass achieved at skeletal maturity.
Calcium can be obtained from a variety of dietary sources. The primary sources of calcium are dairy products, in particular milk. However, beginning in young adulthood and continuing through later life, milk is typically not consumed in sufficient quantities by the general population to obtain needed levels of calcium. This may be caused by lactose intolerance as well as by the unattractiveness of milk as a drink for "social occasions."
To achieve a greater consumption of calcium throughout life, more appealing alternatives to milk are needed. Such beverages must be consumed in sufficient quantities to provide nutritionally beneficial amounts of calcium. Therefore, non-dairy product beverages which comprise a milk level of calcium, 0.12% by weight, are in demand. To this end, soft drinks and fruit juice products have been devised which are fortified with calcium.
In order to save on shipping and packaging costs, concentrated beverages are preferred. These beverages are diluted at the time of consumption. Greater than 5-fold concentrates are highly preferred for economic reasons. However, as these beverages become more concentrated, the water level decreases therefore making it more difficult to solubilize calcium and sugar.
British Patent 2,207,335, Buisson et al., published Feb. 1, 1989, discloses three-fold to five-fold beverage concentrates comprising solubilized calcium; an edible acid component comprising citric, malic, fumaric, adipic, gluconic, tartaric and lactic acids; chloride and a flavor component containing no more than 20% fruit juice on a single strength basis.
U.S. Pat. No. 4,722,847, Heckert, issued Feb. 2, 1988, discloses three-fold to five-fold calcium supplemented fruit juice concentrates which are substantially free of added protein. The concentrates comprise solubilized calcium, an acid component comprising a mixture of citric and malic acid in specific ratios, at least 45% fruit juice, a sugar content of about 6.degree. to 75.degree. Brix and no more than about 0.7% chloride ion.
In developing alternatives comprising a milk level of calcium, several concerns have arisen, the first of which is stability. Due to the level of calcium salts in the beverage concentrates necessary to achieve a milk level of calcium, the precipitation of insoluble calcium salts, particularly at high temperatures, is a problem. Stability at high temperatures, greater than 90.degree. F. (32.degree. C.), is particularly important for storage in unair-conditioned warehouses, particularly in tropical environs, and for storage near heat sources such as those found in commercial kitchens.
Another concern is developing a calcium supplemented beverage which has desirable taste and mouthfeel qualities. The inclusion of high levels of calcium imparts significant "chalky" and/or "biting/burning" mouthfeel sensations. In addition, the inclusion of chloride ion imparts a bitter note to the flavor. In addition to providing consumer acceptable taste, the beverage needs to be visually appealing to the consumer. The inclusion of significant levels of calcium often produces a cloudy, opaque beverage. All of these concerns are further complicated by the low level of solubilizing water in greater than 5-fold beverage concentrates.
It is an object of the present invention to provide greater than 5-fold (5 X) beverage concentrates which are nutritionally supplemented with calcium, are stable at high temperatures and have a consumer acceptable taste and mouthfeel as well as a soluble system, i.e., free from calcium or sugar solids.